1. Field of the Invention
The present invention relates to a driver for displaying display data and a display device using the driver.
2. Description of Related Art
A display device such as a TFT (Thin Film Transistor) liquid crystal display device, a simple matrix liquid crystal display device, an electroluminescence (EL) display device, and a plasma display device becomes widely used. Each of these display devices includes a display portion and a driver for displaying display data on the display portion.
As techniques related to the driver, Japanese Laid-Open Patent Application JP 2005-215007A and Japanese Laid-Open Patent Application JP-Heisei 07-78672A disclose drivers which are able to switch the number of outputs (the output number) based on resolution of the display portion. These drivers employ a configuration in which an output number control signal for switching the output number is supplied from outside to the driver that does not include an output number switch function for switching the number of outputs.
We have now discovered the following facts. As described above, for example, in a case where the output number of the driver can be switched to one of a first output number and the second output number, the drivers described in JP 2005-215007A and JP-Heisei 07-78672A are required to supply the output number control signal indicating one of the output numbers to the driver. In this case, it is also required to provide an output number control terminal for supplying the output number control signal on a chip. However, in a case where the output number of the driver is not switched, it is not required normally to provide the output number control terminal on the chip.
In the case where the output number of the driver is switched as described above, since the output number control terminal is provided on the chip, it is required to mount a device for supplying the output number control signal to the output number control terminal and a device for setting a signal level of the output number control signal in a display device. In this case, wirings are also needed for connecting the above mentioned devices to the output number control terminal. This prevents a frame of non-displayed area portion on a periphery of a liquid crystal panel from being narrowed. In addition, costs are required for mounting the above mentioned devices and for wiring them.